Supporting arm for a wiper blade



FIG. 1 is a front perspective view of a supporting arm for a wiper blade showing my new design;

FIG. 2 is a top view threof;

FIG. 3 is a side view thereof;

FIG. 4 is an end view thereof;

FIG. 5 is the opposite end view thereof of FIG. 4;

FIG. 6 is the opposite side view of FIG. 3 thereof; and,

FIG. 7 is a bottom view thereof. 

The ornamental design for a supporting arm for a wiper blade, as shown and described. 